“An illusion produced by duplicating facial parts, which can cause an unstable feeling for many observers, was investigated. We examined factors that contribute to the unstable feeling. The results suggest that this illusion is specific to face perception, and the unstable feeling may be generated by difficulty in keeping attention directed to either of the duplicated facial parts.”
Bonus figures from the full text:
Discoblog: NCBI ROFL: No way. According to my tongue, that hole is definitely wider. (That’s what she said.)
Discoblog: NCBI ROFL: Think all cows look alike? Then clearly you’re not a cow.
Discoblog: NCBI ROFL: Hmm… I wonder if this illusion works on other body parts?
NCBI ROFL. Real articles. Funny subjects.
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